London: Britain`s political leaders planned to campaign through the night on Tuesday in a final push for votes, two days before a Parliamentary election that opinion polls suggest will be the closest in nearly 20 years.
Prime Minister Gordon Brown`s ruling Labor Party, in power since 1997, trails the opposition Conservatives by seven and 11 percent before the May 6 vote in the two latest opinion polls.
That could give David Cameron`s center-right party a slim majority in Parliament or leave him just short of taking overall control of the lower house, depending on how the votes are spread across Britain`s 650 electoral districts.
Cameron, under pressure to end his party`s 13 years in opposition and secure a solid majority, will campaign overnight on Tuesday, seeking support from the third of voters said to still be undecided.
"We are taking absolutely nothing for granted," George Osborne, the Conservatives` finance spokesman and election coordinator said in a message to supporters. "I want us to fight to persuade every single voter that is still undecided."
The Financial Times newspaper gave Cameron a boost, switching its support from Labor to the Conservatives. It said Cameron`s party will be better at tackling Britain`s record budget deficit.
Brown, expected to match Cameron`s unprecedented campaign marathon, said the Conservatives would cut public services and threaten Britain`s recovery from the worst recession since World War Two.
"Their slogans may be modern, but their policies are those of the 1930s and the 1980s," Brown wrote in the Guardian newspaper.
Two of his senior ministers appeared to appeal to center-left Labor supporters in some close-fought electoral districts to consider voting for the third party, the Liberal Democrats, to undermine the Conservatives.
Welsh Secretary of State Peter Hain said Labor voters in marginal seats where either the Lib Dems and the Conservatives were likely to win, should "vote with their heads not their hearts". Schools Secretary Ed Balls said he wanted to "keep the Tories (Conservatives) out" in very close districts.
The final Reuters/Ipsos MORI marginals poll, which surveys voters living in the kind of constituencies held by the ruling Labor Party the Conservatives need to win for a majority, shows support for the parties in these seats was neck-and-neck.
That represents a 7 percent switch in support to the Conservatives from Labor compared to the 2005 election and could be just enough to put them into power in the 650-seat Parliament.